Calculating-machine.



A. BURKHARDT.

CALCULATING MAGFINE.

APPLICATION FILED APR. 2a. 1900.

951,982. Patented Mar. 15,1910.

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CALCULATING MACHINE.

APPLICATION FILED APR. 28, 1900.

951,98% I Patented Mar. 15,1910.

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UNITED STATES PATENT OFFICE.

ARTHUR BURKI-IARDT, or GLASHfi'I TE, GERMANY, ASSIGNOR, BY MESNE AssrenMENTS, TO AGTIEN-GESELLSCHAFT VORM. SEIDEL & NAUMANN, OF DRESDEN, GER-MANY, A CORPORATION OF GERMANY.

CALCULATING-MACHINE.

Specification of Letters Patent.

Patented Mar.'15, 1910.

Application filed April 28, 1906. Serial No. 314,295.

To all whom it may concern:

Be it known that I, ARTHUR BURKHARDT, engineer, a subject of the King ofSaxony, and a resident of Glashiitte, in the Kingdom of Saxony, Germany,have invented acertain new and useful Improvement inCalculating-Machines; and I do hereby declare the following to be afull, clear, and exact description of the invention,such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to numeralsof reference marked thereon, which form a part of this specification.

My invention relates to improvements in calculating machines; and theobject of my improvements is to providev a machine of this class inwhich, by a sim le mechanism,

the adding wheel is operate according to the digit struck, by amechanism common toall of the digits of one column.

My invention also consists in providing,v

in the machine described, means to lock the keys in their depressedposition in which they control the operating means for the adding wheelin such a way that the proper rotation is transmitted to the latter. Thelocking means are constructed in such a way that, by depressing one keyanother one which might still be locked after the prevlousoperation ofthe machineis automatically released, so that it returns to itsinoperative position.

Further my invention consists in so connecting the operating means forthe adding wheel that, at the end of each operation of.

the machine, all the keys of the different columns of digits areautomatically released.

Anexample of a calculating machine embodying my invention is illustratedin the accompanying drawings in which similar numerals of referencerefer to similar parts throughout the different views.

In said drawings Figure 1 is a cross section through my improvedmachine, showing the keys, the means to rotate the adding wheel, and themechanism operated by the keys, whereby the revolution of the addingwheel is controlled. Fig. 2 is a plan of Fig. l, a part of the top plateor cover of the machine being broken away. Fig. 3 is a cross section ofa part of Fig. 1 on a larger scale, illustrating in detail the'lockingmeans for beveled wheels 12 an In the example illustrated, the casin ofthe machine consists of a top plate 1, a ase plate 2, side plates 3, afront plate 4, a rear plate 5, and a partition wall 6. Within thechamber formed by the partition wall 6 and the rear plate 5, addingwheels 7 are mounted on a vertical shaft 8 supported by the top plate 1.The number of the adding wheels corresponds to the number of columns ofdigits and varies according to the maximum number to be registered bythe machine. The digits marked on the upper surface of the adding wheelscan be seen through openings 9 in the top plate. The adding wheel isformed with a sleeve 10 by means of which it is connected with a beveledwheel 11, which can be enga ed by either of two 5 13 mounted on a commonsleeve and ada ted to be moved longitudinally on a sha 14 by anypreferred means, said beveled gearing 11, 12, and 13 providing a clutchmechanism, whereby the shaft 14 can be coupled with the adding wheel 7to revolve the latter for the purpose of adding or subtracting a certainnumber. The shaft 14 rotates 111 suitable bearings of the plates 5 and6, and of a bracket 15 on the front side of the casing. It is providedwith nine co wheels 16 mounted thereon, so as to sli e longitudinally;but rotation will be transmitted by the cog-wheels to the shaft, thelatter be ng made, in this example, of square cross section.

Mounted on the bracket 15 and the wall 6, parallel to the shaft 1 1,there is a drum 17, having a plurality of toothed segments 18 ofdifferent lengths, mounted on its periphery, every one of whichcooperates with and can be brought into en agement with one of thecog-wheels 16. T e length of said segments corresponds to the numberwhich it is intended to register on the adding wheel. The drum 17 can berotated, at each operation of the machine, by any suitable means. In thepresent instance a beveled gearlng 19, 20 is provided, whereby the drumis 0peratively connected with a shaft 21, adapted to be rotated by acrank 22 or the like. In a similar way, corresponding drums 17 for eachof the columns of digits are connected with the shaft 21, so that allthe drums will be simultaneously rotated upon operation of crank 22.

Extending through suitable slots of the top plate 1 and of an additionalguide plate 23, supported on the walls 4 and 6, there are several rowsof keys 24c, nine being provided for each column, which keys have thenumbers one to nine, marked on their heads. By means of these keys, thecog-wheels 16 can separately be brought into engagement with the toothedsegments 18. For this purpose, they are provided with bell crank levers25 which have their fulcrums on shafts 26 extending from side to side ofthe machine. With their free ends, thelevers 25 are pivotally connectedwith rings 27 engaging sleeves 28 of the cog-wheels 18. Normally thekeys 24 are held in their retracted position by springs 29.

In order to lock the keys in their depressed position, in which acog-wheel enages its segment 18, I provide a slide 31 or each column,which extends from the front to the rear of the machine, and engages thekeys 24 by slots 32. A spring 33, or the like, has the tendency to pullthe slide toward the front side of the machine. Adjacent to the slide,and cooperating therewith, I provide a lug 34 on each key, which lug, byan inclined portion, is adapted to move the slide laterally against theaction of the spring 33. When, however, the key has assumed itsdepressed position, it will be locked by the slide, which is pulled backby the spring and thereby forms an abutment for the upper part of thekey 24. It will be noticed, that, upon operation of one of the keys 24:,another one which may still be in its depressed ositionwillautomatically be retracted by its spring 29, at the mo ment theslide is moved, by the operated key, into its extreme rearward position.This arrangement .is also advantageous, when, by mistake, a wron key hasbeen struck. In such a case it Wlll. but be necessary to strike thecorrect one, whereby the wrong one will automatically assume itsretracted position.

In order to release the keys of all the columns at the end of eachoperation of the machine, I provide the following mechanism: Mounted insuitable guides 35, and extending crosswise of the slides 31, there is abar 36 actuated by a sprin 37. It is provided with suitable slots 38aving inclined sides 39 engaging pins 40 of the slides 31. Normally thebar 36 is held by the spring 37 in a position in which it does notengage the slides 31. But in order to release the keys it is engaged bya rocking lever 42, having a pin or the like extending through a slot 41or' the top plate, which pin can either be actuated by band, or, as inthe example illus trated automatically by the crank 22.

In Fig. 4, I have illustrated a modification of the connection of thekeys 29 and the cog-wheels 18. In this exam le, the keys are formed witha lower inc ined portion having a slot 43 formed therein. Said slotengages the ring 27 of the sleeve 28, so as to move the cog-wheel 16sidewise and into engagement with its segment 18.

The operation of the machine is as fol lows: It will be understood thatthe mechanism described above with reference to one adding wheel is thesame for all the wheels. Now, to register a number on the machine, theoperator strikes one of the keys of each column according to the digitto be registered, as is well known in the art. By thus striking a key,one of the cog-wheels will be brought into engagement with its segment18, the length of which is proportional to.the number marked on the key.Should a mistake occur, the operator will just strike the correct key,whereby the wrong one automatically returns into its inoperativeposition. When the keys indicating the number to be registered aredepressed and locked by the slides 31, the operator turns the crank 22,which rotation is transmitted through the shaft 21, and gearing 19, 20to the drum which will perform a full revolution. The segment engaged bya Wheel 16 will therefore rotate the latter according to the length ofthe segment 18, which ro tation will be transmitted to the adding wheel7.- At the end of the operation of the crank 22, all the keys will bereleased by the crank striking the lever 42. Then the operation can berepeated.

The mechanism to transmit a partial revolution at the end of a completerevolution of one adding wheel to the next succeeding one may be of anypreferred construction.

I claim;

1. In a calculating machine, the combination, with a plurality of addingwheels, of operating means therefor, a selecting mechanism comprisingrows of de ressible keys, means to lock said keys in t eir depressedposition comprising slides movable longitudinally of the rows of keys,pins carried by said slides at their ends, and a releasing bar for saidslides extending transversely thereof and having recesses with inclinedsides fitting ,over said pins.

2. In a calculating machine, the combination with adding mechanismembodying a plurality of adding wheels, of selecting mechanismcomprising rows of depressible keys having projections, there being onerow of keys for each adding wheel, independent slides for each row ofkeys to lock the latter in depressed position and moved in one directionto lock the keys by the projections on the said keys, the keys beingmovable through the slides, a releasing mechanism for the slides andkeys consisting of a bar extending senses across and engaging portionsof the said slides, means controlled by the depression of the keys foroperating the adding mechanism, difi'erential mechanism having meanscooperating with each row of keys, and means movably connected to thelower extremities of the keys and engaging different portions of thedifferential mechanism to set said portions in accordance with the keyoperated.

3. In a calculating machine, the combination with adding mechanismincluding a plurality of adding wheels, of selecting mechanismcomprising rows of keys for each adding wheel, means for locking thekeys of each row in depressed position, a shaft having a plurality ofgear wheels shiftably mounted thereon, means connected to the keys andto said gear wheels,-shifting connecting means between the keys and saidgear wheels, and an exteriorly operative drum for each set of gearwheels and provided with segments of different lengths for engagement bythe gear wheels.

4. In a calculating machine, the combination with an adding wheel, ofselecting mechanism comprising depressible keys,- means to lock saidkeys in depressed position, releasing means embodying a lever carrying aprojection, and mechanism for operating said adding wheel and includingmeans which abuts against said projection and actuates said releasingmechanism.

5. In a calculating machine, the combination with an adding wheel, ofselecting mechanism comprising a row of depressible keys, a slidethrough which said keys have movement to lock the keys in depressedposition, the slide being movable in one direction by the depression ofthe keys and having means for automatically moving it in the oppositedirection t6 lock the keys after the latter have been depressed acertain distance, a releasing bar for said slide having a levercooperating therewith and provided with a projection, operatingmechanism for said adding wheel, and a crank coacting with a part ofsaid mechanism and with said lever to operate the releasing bar.

In testimony, that I claim the foregoing as my invention, 1' have signedmy name in presence of two subscribing witnesses.

ARTHUR BURKHARDT.

Witnesses PAUL AREAS, PAUL HERRMANN.

